This invention relates to an ink cartridge for supplying ink to a record head, and an ink jet record apparatus using the ink cartridge.
An ink jet record apparatus generally comprises a record head mounted on a carriage and moving in the width direction of record paper, and paper feed means for moving the record paper relatively in a direction orthogonal to the move direction of the record head.
Such an ink jet record apparatus prints on record paper by ejecting ink droplets from a record head based on print data.
A record head capable of ejecting black ink, yellow ink, cyan ink, and magenta ink, for example, is mounted on a carriage, and in addition to text print in black ink, full-color print is made possible by changing the ink ejection percentage.
Thus, ink cartridges for supplying black ink, yellow ink, cyan ink, and magenta ink to the record head are placed in the main unit of the apparatus.
In the ordinary ink jet record apparatus, the ink cartridges for supplying black ink, yellow ink, cyan ink, and magenta ink are mounted on a carriage, and are moved together with the carriage.
On the other hand, in this kind of record apparatus provided for an office or business, for example, to deal with a comparatively large amount of print, the large-capacity ink cartridge storing each ink is not placed on the carriage and is placed in the apparatus main unit.
A record apparatus of the type wherein main tanks as ink cartridges are placed in the apparatus main unit (cartridge holder), and subtanks are placed on a carriage on which a record head is mounted is also provided. Ink is respectively supplied from the main tanks to the subtanks via ink supply tubes, and further from the subtanks to the record head.
In such a record apparatus, to improve throughput, such a function is required that can replenish ink from the main tanks to the subtanks in succession to stably supply ink from the subtanks to the record head, while print is executed.
By the way, nowadays, demand for high-accuracy print quality grows, and there is a tendency of using ink containing pigment (pigment ink), for example, as print ink.
Such pigment ink has a large particle diameter of color material as compared with ink containing a dye (dye ink), and pigment is likely to be collected and concentrated in the bottom portion of a cartridge (ink storage chamber), and therefore a concentration distribution (non-uniformity in concentration) easily occurs in the ink in the cartridge.
Thus, there arises a technical problem in that the ink in the cartridge is not sufficiently mixed at the use time and uniform print density and quality cannot be obtained.
It is therefore an object of the invention to provide an ink cartridge for making it possible to sufficiently mix ink in the cartridge at the use time and therefore provide uniform print density and quality. Another object of the present invention is to provide an ink jet record apparatus using the ink cartridge.